Telephone accessory



July 3, 1928. 1,675,622

D. S. S. STEUART TELEPHONE ACCESSORY Fild Nov. 17, 1927 4 Sheets-Sheet 1 I we wiar:

.20 u- Z-a 5 fluff .506: fiauarl July 3, 1928.

D. s. s. STEUART TELEPHONE ACCESSORY Filed Nov. 17, 1927 4 Sheets-Sheet 2 July 3, 1928..

D. S. STEUART TELEPHONE ACCESSORY Filed Nov. 17, 1927 4 Sheets-Sheet 3 Inn/anfar;

2041 712.: ffurf 90a: ffzuarl' Jul 3, 1928.

D. S. S. STEUART TELEPHONE ACCESSORY Filed Nov. 17, 1927 4 Sheets-Sheet 4 Patented July 3, 1928.

T T STATESv i PA ENT OFFICE.- 1

DOUGLAS STUART SPENS STEUABT, OF LONDON, ENGLAND.

'rnmrnonn nocnssonr.

Application filed November 17, 192?, seria no. 283,978, and in Great Britain June 14, 1926.

. The present invention relates to an improved arrangement for supporting and con? structing a flexible tube attached to a teler phone transmitter. y

6 In my Patent No. 1,654,193, granted Dec. 27,1927, I have described an arrangementby which a flexible. tube extending from a transmitter can be adjusted to sta inany position to which it is put, such tu e carrys mg at its outer end a mouthpiece and enabling Conversation to take place without bringing the telephone right up to the mouth of the user. i The present invention, while it mainly l contemplates improvements in a device of' this character, also discloses ideas which are of a much broader scope. l One of the features of the present invention concerns the construction and design of the flexible tube which should taper outwards from the transmitter.

Another feature of the invention concerns the shape of the mouthpiece, which instead of being flared should preferably be cup-shaped.

A third feature of the invention concerns shutter arrangements; one which is manually operated for preventing the sound passing down flexible; tubes to the transmitter and which can be controlled at will bythe user, and a second which is automatically controlled to prevent dust getting into the receiver. v

This latter feature is usedlparticularly in conjunction with the fourthfeature of the invention which consists of an attachment between the receiver and the mouthpiece whereby when the receiver is placed to the ear the mouthpiece automatically comes in front of the mouth. j

A fifth feature of my invention, which may be capable of considerably broader application, is a flexible wire arrangement by means of which the flexible speaking tube as can be supported in any desired position.

This arrangement consists of strandedaluminium wire surrounded by a flexible tube and serves to support the speaking tube by simply threading it, through the tube. No

claim for this arrangement per se is made in.

the present case, however, as it constitutes the subject matter of a divisional application ffiled December 27, 1927, Serial No. 242,941. 1 1. .The above and other features of my in-.

vention willbe better understood by referring. to the accompanying drawings, in wmehri 1 shows theapplication of the inventionfto {a illar-type telephone of standard design; ig. 2is a side view of, the clamp 10 and its support; Fig. .3is a longs tudinalfsection of the tube and mouthpiece; Fig. 4 is an enlarged sectional view. of a portionof the tube; Fi 5 shows anarr angementfor securing t e tube to a transmitten when the usual mouthpiece is removed; Fig. 6 shows an alternative arrangement for securing the supporting wire to that illustrated inFig. 3.; Fig.7 shows the application of'the invention to an instrument' of the handset type; Fig. 8 shows the manner in which the transmitter is fitted in the box usedin the type of instrument illus trated in. Fig. I Fig. 9 is a face view ofthe shutter 11; while Fig. 10 shows a section of the earpiece or cup of the receiver 17 with an automatically operating. shutter.

Referring'to Fig. 1,.normal1y the pillartypej. telephone 12 rests withits base upon a sloping it stand. This stand is provided withwa projection and with an upwardly extendings ocket, inwhich isfitted a bent rod, 40L The fitis a tight one so that the rod 40 can only be removed and replaced by exerting an appreciable force, so that normally it will beheld tightly. The rod 40v at its upper endcarries a socket 41 in which a bent1rod42 (see Fig. 2) whichscrews into a threadin the clamp 10 is adapted to slide up and down, being secured in the desired position by means of a screw 43. The clamp 10 isior thepurpose of securing the ferrule 13 in a suitable position to engage the transmitter mouthpiece 35. The ferrule 13 is fitted on to the end of a flexible tube 14, the

securing of the clamp to the ferrule being the pillar-type telephone, the arrangement being such that when the transmitter is placed on the stand, it tilts, due to the slope of the stand msuch a direction as to press against the spongy rubber collar 34. This spongy rubber collar is shaped to corres 0nd with the shape of the inner flare 0 the transmitter mouthpiece 35, and consequently an automatic sealing between the ferrule and the mouthpiece is made when the telephone is placed .onthe stand as shown,.providing of course the position of the clam 10 and the ferrule have been suitably a justed previously. The usual receiver 17 is supported by meansof a clamp 18 attached toa rod 19 screwed into a light aluminum body 20 shaped as shown, that is, of a suitable shape to engage with the switchhook 21. By this means it is possible to operate the switchhook andsupport the receiver in the switchhook by placing the body 20, instead of the receiver, in the switchhook. From the upper end of the body 20'extends a bent rod 22 carrying at its end a ferrule 23 and a flexible link 24, which link terminates in a sliding collar 25 embracing the ferrule 26 secured to the end of the flexible tube 14. The flexible tube 14 terminates in a casing 11. In this casing (see Fig. 9) is a shutter device consisting of levers 27 and 28 which, when pressed together, cause the shutters 28" and 29 to close the passage from the tube 14 to the mouthpiece 30. A leaf spring 31 normally holds the shutters 28" and 29 apart, so that only when the arty using the telephone presses the levers 2i and 28 can the transmitter be rendered dead. This mouthpiece is slightly bent, as shown, and the arrangement is such that when the receiver is lifted and placed to the ear the collar 25slides along the ferrule 26 and engages at its recessed side a boss on the mouthpiece. Thisarrangement ensures that the mouthpiece 30 is held inia suitable position so as to be brought automatically in front of the mouth. This enables conversation to be carried on at some diStflIlCQIfIOII] the instrument and consequently the pillartype instrument may rest a foot or two away from the speaker, leaving his'desk clear for. writing or reading. The flexible link 24 may be of any known type which will remain in the position to which it is put,"but preferably it is constructed of aluminium wires stranded together and covered with a flexible'itube to prevent-bulging of the individual wires. Such an arangement is practically free from a tendency to return to the position'from which it is moved,

while at the same time it tends to resist movement and so holds the mouthpiece in the position to which it is placed. The receiver 17 in the position shown might conceivably collect dust which in time might seriously impair its operation. In order to avoid this defect according to the invention an automatically operating shutter is pro 'vided in the receiver cap 32. Fig. 10 shows a view of the inside of the cap, from which can be seen the loosely pivoted shutter 33 supported on a pivot at the right side of the cap, that is, when one islooking at the receiver with the cap end infront. Conseuently when the receiver is supported, as

its own weight and rests on the stop 34 and closes the opening 34 in the cap (see the dotted-line position in Fig. 10), thus making thereceiver dust proof. When the receiver is lifted and held to the car it will be noted that the receiver is reversed and the shutter falls to the position shown in full lines in Fig. 10 so that the opening 34 is cleared and hearing is in no way aflected.

Fig. 3' shows in detail the construction of thetube 14, the ferrule 13 and the mouthpiece 30. For convenience the shutter 11 is omitted, as is also the collar 25. In certain cases 'it'may be desirable not to have any connecting link between the receiver and the mouthpiece, and in such a case the arrangement shown in Fig. 3 could be used exactly as it is. On the other hand it will be readily understood that the arrangements disclosed in Fig. 1 could be incorporated in Fig. 3; in fact Fig. 3 simply explains those details of construction which are not sufficiently shown in Fig. 1.

A description will first be given of the construction of the tube 14. This element is important both as regards its dimensions and as regards its actual structure. As to dimensions, it has been found that the best and most efficient results can be obtained by arranging for the tube to taper slightly so that its-diameter at the transmitter end is somewhat less than its diameter at the mouthpiece end. A design of tube which has been found to give most satisfactory re sults is one in which the diameter of the tube at the transmitter end is andat the mouthpiece end is 1%", this taper being for a tube having a length of 13%. For a different length of tube the taper would be proportionate to what it is in the above mentioned case. The inner diameter of the ferrule 13 is so arranged as to continue this taper, which is however slightly accentuated right to the transmitter diaphragm. In the case shown the ferrule 13 is formed of: a single casting, which is threaded at one end, and into which the tube 14 is fitted and finally cemented in position, while at the other end it is recessed and fitted with the spongy rubber collar .34 shaped to engage in the inner flare of the transmitter mouthpiece 35.

As regards composition, the construction of the tube will be better followed by reference to Fig. 4; It consists of a closely wound spiral of steel wire 51 embedded in a sheath 52 of pure rubber latex. Outside .S owninFig,v 1, the shutter 33 falls under the sheath 52 is albrading 53 of silk or like material, which is applied at considerable pressure. Such tubing is highly flexible and is very efficient for sound transmission, and while it constitutes a preferred construction, the invention is notspeciflcally limited thereto as other Constructions could be used which might: have theadvantage of greater cheapness. The design of a speaking tube is well known and any eflieient design of speaking tube known could be used with this invention without departing from the spirit thereof. Itis apparently important that the wire 51 should-be of steel as aluminium wire has been tried and found not to give near ly as efficient a result. Aluminium alloys of the duraluminium type have been tested and found to give good, results and might be used in place of steel where lightness is essential. Itis not essential that the wires 51, however, should be so constructed that the successive turns of the spiral touch each other, as good results can be obtained where thespirals are separated bysome little distance. The flexible tube is supported in the ferrule 26 in much the same way as in the ferrule 13, that is, it is threadedin said ferrule 26 and then cemented in position. On this ferrule is fitted the mouthpiece 30 which is made to have a tight fit so that it can be placed on and removed without using a tool-and yet is firmly held. The shape of the mouthpiece is. important to give efficient results. It is shown slightly curved, this being because it is more convenient that it should rise slightly towards the user, but

there may he circumstances in .which it would be; advantageous for it to be straight. However, the importance of the shape is not so much in the fact that its axis is bent as in the fact that the mouthpiece is not flared in the same wayas the transmitterhmouthpiece .35, that is, in the someway as the usual mouthpiece, but :is made ,more cupshaped' so that actually the flare first. increases and then decreases, whereas in the ordinary mouthpiece it increasesmore and more. Actually, in fact, the extreme end of the mouthpiece is substantially parallel to the axis. In order to support the tube 14 a flexible wire arrangement 54 is provided, whichis similar in construction to the flexible link 24. This flexible wire 54, as shown, also consists of anumber of carefully annealed aluminium wires 55'st-randed together and tightly covered byJa flexible tube 56 so asto prevent the strandedwires bulging when the flexible wire is bent. The flexible tube 56 is ofwell known construction consisting of an interlocking; helical winding. The aluminium wires are highly flexible andvca-n be bent as desired andstay in the positionin which they are put; Theflexible tube round them secures them in position so; that they cannot bulge and so enables aconsiderable weight tobe supported at some distance fromthe mouthpiece. .This has the advantage that the mouthpiece may be supported independently of the flexible link24,,whenl once it is adjusted to a suitable tube 56, which sliding is necessary to allow forfree play when the tube 14 is bent. Actually apin 59 could be provided in addition to the pinching, or separately therefrom, but the pin 59 by itself, itshould be men tioned, is somewhat unsatisfactory in view of the flexible wire 54 being stranded, and

it is found that by pressing the thin tube 57 twice, as shown at 60, the flexible wire 54 canbe satisfactorily secured in position, The tube 57 has soldered to it, or secured in any otheriway, a threaded ring 61 whichthreads into the ferrule 13 and so anchorstheflexible wire 54 centrally within the tube 14. Furthermore, the tube 57 extends beyond ring61 and ishere tapered so as to give free passage to the sound waves, this tapering finishing in a fine point just op posite the'diaphragm 62 of the transmitter. The threaded ringfil has three arms extending from its boss, which latter is secured to the member 57, these arms being so shapedas to'be tapered in both directions along the tube and sooffer no interference to thepassage of the sound waves from the mouthpiece to the transmitter. The wire 54 is supported.centrallywof :tube 14 at the mouthpiece end of the latter by the tube 58, the tube 58 being provided with a threaded ring 63 similar to ring 61, which threads into the ferrule 26. The tube 58 extends axially with respect'to'the mouthpiece 30 and terminates in a cap 64, which cap is fitted with a wick arrangement for carrying disinfectant and is placed in the perforated tube 58 to automatically keep the mouthpiece free from germs. In the mouthpiece 30 a spiral leaf spring 65 is provided which, it is found, in a very satisfactory manner prevents blasting or other loud noises from affecting the transmitter, and generallyseems to considerably improve. the speech a transmitter.- to assist in the support of the mouthpiece 30, and. furthermore to guard against the tube 14 beingunduly strained. at the part where it engages the ferrule 13, a stiff spiral spring 66is utilized which is provided with; an up- In order ward bend, as clearly shown in Fig. 3. This spring 66 is anchored on a ring 67 at one end of the ferrule 13. The arrangement as shown and described has proved from experimental tests to be highly efiicient for sound transmission and enables the transmitter to receive sound, even when the mouth is two or three inches away from the mouthpiece, as loud as when the speaker has his mouth right up to the ordinary mouthpiece in accordance with the instructions he receives from the telephone operating authorities;

Fig. 5 shows an alternative arrangement where the ferrule 13 screws directly into the casing 16 of the transmitter, that is, where the ordinary mouthpiece is removed.

In this case it is possible to connect a wire 68, which may be spiral or otherwise, from the tip of the tapered tube 57 to the nut 69 by which the transmitter capsule is connected to the diaphragm 62. This is of advantage because a certain amount of the sound transmitted down the mouthpiece is actually transmitted along the flexible wire arrangement to the tube 57, and furthermore transmission of sound through metal is so much more efiicient than the transmission of sound through air that an appreciable magnification of the sound can be obtained.

Fig. 6 shows an alternative arrangement for anchoring the flexible wire 54. The stranded wires 55 in this case are bent round so as to extend first in a radial direction through a slot in the ferrule 13 and then in a circumferential direction in a groove 70. The ferrule 13 is threaded in a similar manner to that shown in Fig. 4, so as to engage with the transmitter casing .16, but the thread in this case is made somewhat longer so that a nut 71 can be screwed on to secure the stranded wires 55 in position. The ferrule can then be screwed into the casing 16. A recess 72 is bored in the end of the ferrule 13 so that a fine spiral spring 73 can be fitted therein. This spiral spring73 serves the same purpose as the spiral spring 65, but in this case it is provided near the transmitter instead of in the mouthpiece. If desired, of course, spiral springs can be provided at both ends. It is found that the width of the material forming the spiral spring, that is, the dimension parallel to the axis, should be appreciable, say at least and even as much as A or larger.

Figs. 7 and 8 show a modification in which the receiver 101 is of the watch type, and herefore the whole arrangement can be made to resemble a handset, except of course that the transmitter is not portable. The switchhook could then take the form of a cradle switch of known type. The instrument would therefore comprise a handle 100, through which passes a tube 102,-to which the receiver 101 is seeuredat one end, while the other end is bent and has secured to it a clamp 103 by means of a screw 104. The clamp 103 when tightened up is free to rotate on the ferrule 105, but prevented from having longitudinal motion by means of the collars 106 and 107. The mouthpiece 108 is secured to the ferrule 105 at one side while the other side of the ferrule is secured to a flexible tube 109 of similar design and structure, and similarl proportioned to the flexible tube illustrate in Fig. 3. The flexible tube 109 terminates at its other end in a ferrule 110, which is tapered at its inner end as seen in Fig. 8, and provided. with a thread for engaging with the transmitter casing 111. The transmitter casing is mounted inside the instrument box 115 by means of a bracket 113,-and consequently the transmitter is always vertical and is not liable to damage. A spongy rubber collar 114 is provided in the opening of the instrument box 115 so as to make the joint of the transmitter air-tight. In this way thetransmitter is very well protected from'external sounds, the only sounds which can affect the transmitter being those conveyed through the tubing 109 or by mechanical vibration, and mechanical vibration if present can be readily overcome by arranging that the 'sup- 120, in which the handle 100 can rest. The.

weight of the receiver and handle is such as to operate satisfactorily through the rod 117 the usual contact springs (not shown), so that the construction of the instrument follows general practice. There are, however, two modifications, one being that the handle points towards the user. This will be recognized in that the slopeof the instrument is on the side towards which the handle 100 points. On this slope in an automatic instrument can be fitted a dial switch, or the dial switch may be supported vertically alongside the transmitter. The receiver cord 121 will be seen extending from the receiver through the tube 102 and connected by supporting clips 122 and 123 to' the flexible tube 109 and thence into the instrument in the usual manner through a ferrule not shown. To use the instrument it will be clear that all that is necessary is for the user to take hold of the handle 100 and lift the receiver, when the mouthpiece and the earpiece automatically come into position ready for use. Normally the handset is placed to the left ear, but with the arrangement of the clamp 103 it is possible for the handle to swivel to the other side of the mouthpiece, so that a person wishing to use his right ear could do so without an difliculty,

pose, as shown. a

1. In combination, a telephone trans- Imitter, a mouthpiece, a flexible tube connect- 1 ing said transmitter tosaid nrouthpieoe, and

a self-sustaining flexible support located inside-the: tube "for maintaining said tube and mouthpiece in any adjusted position.

2. In combination, a telephone transmitter, a mouthpiece, a flexible tube, a terrule for connecting one end of said tube to said mouthpiece, a second ferrule 'for connecting the other end of said tubeto said transmitter, a self-sustaining flexible wire support located inside the tube for maintaining said tube and mouthpiece in any adjusted position, and means for securing said flexible wire within said ferrules.

' 3. In combination, a telephone transmitter, a mouthpiece, a flexible tube, a ferrule for connecting one end of said tube to said mouthpiece, a second ferrule for connecting the other end of said tube to said transmitter, a flexible wire support comprising a stranded cable of aluminium wires, and a flexible interlocking helical tube closely surrounding said wires, and means for securing the ends of said support centrally in said ferrules.

4. In combination, a telephone transmitter, a mouthpiece for said transmitter, a flexible tube extending from said mouthpiece to said transmitter, a self-sustaining flexible support inside said tube to maintain thetube and the mouthpiece in any adjusted position, a receiver, and a self-sustaining flexible lin-k connecting said mouthpiece to said receiver so arranged that when the receiver is placed to the ear the mouthpiece comes in front of the mouth.

5. In combination, a telephone transmitter, a mouthpiece for said transmitter, a flexible tube connecting said mouthpiece to said transmitter, a self-sustainin flexible support inside the tube for maintaining said tube and mouthpiece in any adjusted position, an instrument on which said transmitter is mounted, a receiver, a contact operating support for said receiver, a member attached to the receiver and adapted to rest in said support, and a link connecting said member to said mouthpiece arranged so as to bring the mouthpiece in front of the mouth when said member is lifted from said support and the receiver is placed to the ear.

6. In combination, a telephone transmitter, a mouthpiece for said transmitter, a flexible tube connecting said mouthpiece to said transmitter, an instrument on which said transmitter is mounted, a receiver, a contact operating support for said receiver, a rigid attachment to said receiver adapted to rest in said contact operating support,

a and an adjustable li'ak connecting said receiver tosaid mouthpiecearrangediso as to bring the mouthpiece to the mouth when the receiver is placed to the ear;

mitten, .-a mouthpiece tor-said transmitter, a flexible tube connectiuig saidinouthpiece to transmitter, a receiver, a flexible flrlinki counect'mg said mouthpiece :to said receiver, a contact operating switchhook for supporting said receiver, an attachment adapted to engage said support and hold said receiver in an appropriate position relative to said mouthpiece, and an automatically operating shutter device to close the aperture in said receiver when supported by the switchhook and open said aperture when placed to the ear. I

8. In combination, a telephone transmitter, a mouthpiece for said transmitter, a flexible tube connecting said mouthpiece to said transmitter, a self-sustaining flexible support inside the tube for maintaining said tube and mouthpiece in any adjusted position, an instrument on which said transmitter is mounted, a receiver, a contact operating support for said receiver, a member attached to the receiver and adapted to rest in said support, and a connection between said member and said mouthpiece arranged so as to bring the mouthpiece in front of the mouth when said member is lifted from said support and the receiver is placed to the ear.

9. In combination, atelephone transmitter, a mouthpiece for said transmitter, a flexible tube connecting said mouthpiece to said transmitter, an instrument on which said transmitter is mounted, a receiver, a contact operating support for said receiver, a rigid attachment to said receiver adapted to rest in said contact operating support, and

a connection between said rigid attachment and said mouthpiece arranged so as to bring the mouthpiece to the mouth when the receiver is placed to the ear.

10. In combination, a telephone transmitter, a mouthpiece for said transmitter, a flexible tube connectin said mouthpiece to said transmitter, a se f-sustaining flexible support inside the tube for maintaining said tube and mouthpiece in any adjusted position, an instrument on which said transmitter is mounted, a receiver, a contact operating support for said receiver, a rigid attachment to said receiver adapted to rest in said contact operating support, and an adjustable link connecting said receiver to said mouthpiece arranged so as to bring the mouthpiece to the mouth when the receiver is placed to the ear.

11. A telephone construction according to claim 6, in which the adjustable link connects the rigid receiver attachment to the mouthpiece.

12. In combination, a telephone transmit- 7, In "combination, a telephone trans ter, a mouthpiece for said transmitter, a adapted to rest in said contact operating 10 flexible tube comprising a spiral of wire of support, and an adjustable link connecting aluminium alloy of the duraluminium type said receiver to said mouthpiece arranged surrounded by rubber latex and by tightly so as to bring the mouthpiece to the mouth 5 braided fabric for connecting said mouthwhen the receiver is placed to the ear.

piece to said transmitter, .an instrument on In testimony whereof I hereunto afiix my 15 which said transmitter is mounted, a resignature this 7th day of November, 1927. ceiver, a contact operating support for said 7 receiver, a rigid attaehmentto said receiver DOUGLAS SPENS STEUART- 

